Phthalocyanines and Their Use in Ink-Jet Printing

ABSTRACT

Compounds of Formula (1) and salts thereof: 
     
       
         
         
             
             
         
       
         
         
           
             wherein:
           M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or a halometal group;   Pc represents a phthalocyanine nucleus of formula;   
         
           
         
       
    
     
       
         
         
             
             
         
       
         
         
           
             R 1  is optionally substituted alkyl other than methyl: 
             R 2  is H, optionally substituted alkyl or optionally substituted aryl; 
             R 3  is H, optionally substituted alkyl or optionally substituted aryl; 
             R 4  is a group comprising a heterocycle and an ionisable group; 
             L is a direct bond or a divalent linking group; 
             x is 0.1 to 3.8; 
             y is 0.1 to 3.8; and 
             z is 0.1 to 3.8. Also compositions, inks, printed material and in-jet processes and cartridges.

This invention relates to compounds, compositions and inks, to printingprocesses, to printed materials and to ink-jet printer cartridges.

Ink-jet printing is a non-impact printing technique in which droplets ofink are ejected through a fine nozzle onto a substrate without bringingthe nozzle into contact with the substrate.

Colour ink-jet printers typically use four different coloured inks;magenta, yellow, cyan, and black. Colours other than these may beobtained using differing combinations of these inks. Thus, for optimumprint quality, the colourants used must be able to form an ink with aspecific precise hue. This can be achieved by mixing colourants but isadvantageously achieved by used a single colourant with the exact huerequired.

While ink-jet printers have many advantages over other forms of printingand image development there are still technical challenges to beaddressed. For example, there are the contradictory requirements ofproviding ink colorants that are soluble in the ink medium and yet donot run or smudge excessively when printed on paper. The inks need todry quickly to avoid sheets sticking together after they have beenprinted, but they should not form a crust over the tiny nozzle used inthe printer. Storage stability is also important to avoid particleformation that could block the tiny nozzles used in the printerespecially since consumers can keep an ink-jet ink cartridge for severalmonths.

With the advent of high-resolution digital cameras and ink-jet printersit is becoming increasingly common for consumers to print offphotographs using an ink-jet printer. This avoids the expense andinconvenience of conventional silver halide photography and provides aprint quickly and conveniently. However this use of ink-jet printersrequires that the prints should display an outstanding fastness to lightand common oxidising gases-such as ozone. Photographs, once printed, areoften kept on display for years and it has been found that evenapparently small changes in the light and ozone fastness of a print in atest system can correlate to a significant improvement in the fastnessof the image in real life.

Another key factors in determining the colour appearance of an ink-jetprint is the chroma intensity of the component colours and small changesin this can have a profound impact on the quality of the image, this isespecially true when the image is a photographic reproduction.

There are many thousands of known colorants and few have thecharacteristics which enable them to be used in ink-jet inks.

Most cyan colorants used in ink-jet printing are based onphthalocyanines and problems of fading and shade change on exposure tolight and contact with ozone are particularly acute with dyes of thisclass.

Phthalocyanines bearing sulfonate and sulfonamide substituents havefound particular utility in ink-jet printing. These dyes are usuallymade by sulfonating a phthalocyanine pigment followed by chlorinationand then amination/amidation, the resultant product carries sulfo andsulfonamide/substituted sulfonamide substituents in any susceptibleposition (for example see Schofield, J and Asaf, M in Journal ofChromatography, 1997, 770, pp 345-348). However we have found thatcertain phthalocyanines substituted only in the α-position displayadvantageous properties when used in ink-jet printing.

The present invention provides compounds of Formula (1) and saltsthereof:

wherein:

-   -   M is 2H, Si, a metal, an oxymetal group, a hydroxymetal group or        a halometal group;    -   Pc represents a phthalocyanine nucleus of formula;

R¹ is optionally substituted alkyl other than methyl;

R² is H, optionally substituted alkyl or optionally substituted aryl;

R³ is H, optionally substituted alkyl or optionally substituted aryl;

R⁴ is a group comprising a heterocycle and an ionisable group;

L is a direct bond or a divalent linking group;

x is 0.1 to 3.8;

y is 0.1 to 3.8; and

z is 0.1 to 3.8.

M is preferably 2Li, 2Na, 2K, Mg, Ca, Ba, Al, Si, Sn, Pb, Rh, Sc, Ti, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, AIX, GaX, InX or SiX₂, where in X is OH orCl, more preferably Sc, Ti, Va, Cr, Mn, Fe, Co, Zn, Ni and Cu,especially Cu or Ni and more especially Cu.

Preferably R¹ is optionally substituted C₂₋₈alkyl, more preferablyoptionally substituted C₂₋₆alkyl and especially optionally substitutedC₂₋₄alkyl. It is particularly preferred that R¹ carries at least onesubstituent selected from the group consisting of —OH, —SO₃H, —CO₂H and—PO₃H₂.

Preferably R² is H or optionally substituted alkyl, more preferably H oroptionally substituted C₁₋₄alkyl, particularly H or unsubstitutedC₁₋₄alkyl, more particularly R² is H, methyl or ethyl, especially H ormethyl and more especially H.

Preferably R³ is H or optionally substituted alkyl, more preferably H oroptionally substituted C₁₋₄alkyl, particularly H or unsubstitutedC₁₋₄alkyl, more particularly R³ is H, methyl or ethyl, especially H ormethyl and more especially H.

Preferably R⁴ comprises a nitrogen heterocycle, more preferably R⁴comprises a triazinyl radical.

Preferably R⁴ comprises an ionisable acid group more preferably anionisable acid group selected from the group consisting of —SO₃H, —CO₂Hand —PO₃H₂.

Preferably R⁴ is a triazinyl radical bearing substituents selected fromthe group consisting of —SO₃H, —CO₂H and —PO₃H₂.

It is especially preferred that R⁴ comprises a group of Formula (2)

wherein:

-   -   X is selected from the group consisting of —OR⁵, —SR⁵, —NR⁵R⁶;    -   Y is selected from the group consisting of —OR⁷, —SR⁷, —NR⁷R⁸;    -   R⁵, R⁶, R⁷ and R⁸ are independently H, optionally substituted        alkyl, optionally substituted aryl or optionally substituted        heterocyclyl provided that at least one of the groups        represented by R⁵, R⁶, R⁷ and R⁸ carries at least one        substituent selected from the group consisting of —SO₃H, —CO₂H        and —PO₃H₂.

Preferred groups represented by X and Y include —OH, —NHCH₃, —N(CH₃)₂,—NHC₂H₄SO₃H₂, —N(CH₃)C₂H₄SO₃H₂, —NC₃H₆SO₃H, —NHdisulfophenyl,—NHsulfophenyl, —NHcarboxyphenyl or —NHdicarboxyphenyl,—NHsulfonaphthyl, —NHdisulfonaphthyl, —NHtrisulfonaphthyl,—NHcarboxyonaphthyl, NHdicarboxyonaphthyl, NHtricarboxyonaphthyl—NHsulfoheterocyclyl, —NHdisulfoheterocyclyl or—NHtrisulfoheterocyclylz.

It is especially preferred that R⁴ comprises a group of Formula (3)

wherein:

-   -   R⁹ is H or optionally substituted C₁₋₄alkyl;    -   R¹⁰ is H or optionally substituted C₁₋₄alkyl;    -   R¹¹ is H or optionally substituted C₁₋₄alkyl;    -   R¹² is optionally substituted alkyl, optionally substituted aryl        or optionally substituted heterocyclyl carrying at least one        substituent selected from the group consisting of —SO₃H, —CO₂H        and —PO₃H₂.

Preferably R⁹ is H or unsubstituted C₁₋₄alkyl, more preferably R⁹ is Hor methyl especially H.

Preferably R¹⁰ is H or unsubstituted C₁₋₄alkyl, more preferably R¹⁰ is Hor methyl especially H.

Preferably R¹¹ is H or unsubstituted C₁₋₄alkyl, more preferably R¹¹ is Hor methyl especially H.

In a preferred embodiment R⁹, R¹⁰ and R¹¹ are all independently either Hor methyl, more preferably R⁹, R¹⁰ and R¹¹ are all H.

Preferably R¹² is optionally substituted aryl carrying at least onesubstituent selected from the group consisting of —SO₃H, —CO₂H and—PO₃H₂. More preferably R¹² is an aryl group (particularly a phenylgroup) carrying 1 to 3, especially 2, —SO₃H groups.

L, the divalent linking group is preferably selected from the groupcomprising: optionally substituted alkylene, optionally substitutedarylene, optionally substituted cycloalkenylene, and optionallysubstituted heterocyclylene (including optionally substitutedheteroarylene). More preferably L comprises optionally substitutedalkylene, especially optionally substituted C₁₋₁₂alkylene and moreespecially optionally substituted C₁₋₄alkylene. It is particularlypreferred that L comprises a group of formula —C₁₋₄alkylene-Z; where Zis a hetero atom preferably N, it is especially preferred that Lcomprises a group of formula —C₂H₄—NR²⁰—, wherein R²⁰ is H or methyl.

Preferably x is 0.1 to 3, more preferably 0.2 to 2.0. In one preferredembodiment x is less than 1 and in another preferred embodiment x isgreater than 1.

Preferably y is 0.1 to 3, more preferably 0.2 to 2.0. In one preferredembodiment y is less than 1.

Preferably z is 0.1 to 3.5, more preferably 0.5 to 3, especially 0.8 to3.0 and more especially 1.0 to 3.

The sum of (x+y+z) is preferably 3 to 4, more preferably the sum of(x+y+z) is 4.

In a preferred embodiment the substituents represented by x, y and z arebound to the phthalocyanine ring only through the β-position on thephthalocyanine ring.

Preferred optional substituents which may be present on L, R¹, R², R³,R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹ and R¹² are independently selectedfrom: optionally substituted alkoxy (preferably C₁₋₄-alkoxy), optionallysubstituted aryl (preferably phenyl), optionally substituted aryloxy(preferably phenoxy), optionally substituted heterocyclic, polyalkyleneoxide (preferably polyethylene oxide or polypropylene oxide), carboxy,phosphato, sulfo, nitro, cyano, halo, ureido, —SO₂F, hydroxy, ester,—NR^(a)R^(b), —COR^(a), —CONR^(a)R^(b), —NHCOR^(a), carboxyester,sulfone, and —SO₂NR^(a)R^(b), wherein R^(a) and R^(b) are eachindependently H or optionally substituted alkyl (especially C₁₋₄-alkyl).When L, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸ or R¹² comprise a cyclic groupsaid group may also carry an optionally substituted alkyl (especiallyC₁₋₄-alkyl) substituent. Optional substituents for any of thesubstituents described for L, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰,R¹¹ and R¹² may be selected from the same list of substituents.

Particularly preferred compounds of Formula (1) are of Formula (4) andsalts thereof

wherein:

-   -   R¹³ is optionally substituted C₂₋₄alkyl;    -   R¹⁴, R¹⁵, R¹⁶, R¹⁷ and R¹⁸ are each independently H or methyl;    -   R¹⁹ is aryl carrying 1 to 3 —SO₃H groups and optionally other        substituents;    -   R²⁰ is H or methyl;    -   L′ is optionally substituted C₁₋₄alkylene;    -   x is 0.1 to 3.8;    -   y is 0.1 to 3.8;    -   z is 0.1 to 3.8; and    -   x+y+z is in the range of 3 to 4.

Preferably R¹⁹ is aryl carrying 1 or 2—SO₃H groups. More preferably R¹⁹is phenyl carrying 1 or 2—SO₃H groups, especially 2—SO₃H groups.

Preferably L′ is unsubstituted C₁₋₄alkylene, especially —C₂H₄—.

Preferred optional substituents on R¹⁹ are as listed above thoughpreferably R¹⁹ carries no substituents other than the —SO₃H groups.

Preferences for x, y and z and x+y+z are as described above.

In preferred compounds and salts thereof of Formula (4) the substituentsrepresented by x, y and z are bound to the phthalocyanine ring onlythrough the β-position on the phthalocyanine ring.

The compounds and salts thereof of Formula (1) are also preferably freefrom fibre reactive groups. The term fibre reactive group is well knownin the art and is described for example in EP 0356014 A1. Fibre reactivegroups are capable, under suitable conditions, of reacting with thehydroxyl groups present in cellulosic fibres or with the amino groupspresent in natural fibres to form a covalent linkage between the fibreand the dye. As examples of fibre reactive groups excluded from thecompounds and salts thereof of Formula (1) there may be mentionedaliphatic sulfonyl groups which contain a sulfate ester group inbeta-position to the sulfur atom, e.g. beta-sulfato-ethylsulfonylgroups, alpha, beta-unsaturated acyl radicals of aliphatic carboxylicacids, for example acrylic acid, alpha-chloro-acrylic acid,alpha-bromoacrylic acid, propiolic acid, maleic acid and mono- anddichloro maleic; also the acyl radicals of acids which contain asubstituent which reacts with cellulose in the presence of an alkali,e.g. the radical of a halogenated aliphatic acid such as chloroaceticacid, beta-chloro and beta-bromopropionic acids and alpha,beta-dichloro- and dibromopropionic acids or radicals of vinylsulfonyl-or beta-chloroethylsulfonyl- or beta-sulfatoethyl-sulfonyl-endo-methylene cyclohexane carboxylic acids. Other examples of cellulosereactive groups are tetrafluorbcyclobutyl carbonyl,trifluoro-cyclobutenyl carbonyl, tetrafluorocyclobutylethenyl carbonyl,trifluoro-cyclobutenylethenyl carbonyl; activated halogenated1,3-dicyanobenzene radicals; and heterocyclic radicals which contain 1,2 or 3 nitrogen atoms in the heterocyclic ring and at least onecellulose reactive substituent on a carbon atom of the ring, for examplea triazinyl halide.

Acid or basic groups on the compounds of Formula (1), particularly acidgroups, are preferably in the form of a salt. Thus, the Formulae shownherein include the compounds in salt form.

Preferred salts are alkali metal salts, especially lithium, sodium andpotassium, ammonium and substituted ammonium salts (including quaternaryamines such as ((CH₃)₄N⁺) and mixtures thereof. Especially preferred aresalts with sodium, lithium, ammonia and volatile amines, more especiallysodium salts. Compounds of Formula (1) may be converted into a saltusing known techniques.

The compounds and salts thereof of Formula (1) may exist in tautomericforms other than those shown in this specification. These tautomers areincluded within the scope of the present invention.

The compounds and salts thereof of Formula (1) may be prepared by anymethod known in the art.

Preferably the compounds of Formula (1) are prepared by condensing aphthalocyanine carrying sulfonyl chloride groups and optionally sulfonicacid groups with compounds of formula HNR¹R² and HNR³-L-R⁴ wherein R¹,R², R³ and R⁴ are as hereinbefore defined. Many compounds of formulaHNR¹R² are commercially available, for example taurine. Compounds ofHNR³-L-R⁴ may be readily prepared by a person of ordinary skill. Thecondensation is preferably performed in water at a pH above 7. Typicallythe condensation is performed at a temperature of 30 to 70° C. and thecondensation is usually complete in less than 24 hours. The compounds offormula HNR¹R² and HNR³-L-R⁴ may be used as a mixture or condensedsequentially.

Phthalocyanines carrying sulfonyl chloride groups and optionallysulfonic acid groups may be prepared by chlorosulfonating phthalocyanineusing, for example, chlorosulfonic acid and optionally a chlorinatingagent (e.g. POCl₃, PCl₅ or thionylchloride).

When it is required that the substituents represented by x, y and zshould be bound to the phthalocyanine ring only through the β-positionthen preferably sulfonated phthalocyanine is prepared by cyclisation of4-sulfophthalic acid or an analogue thereof. Preferred analogues ofphthalic acid include, phthalonitrile, iminoisoindoline, phthalicanhydride, phthalimide or phthalamide. The cyclisation reaction iscarried out in the presence of a suitable source of ammonia (ifrequired), and (if required) a suitable metal salt, for example CuCl₂,and a base such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

It is particularly preferred that the compounds and salts thereof ofFormula (1) are obtainable by a process that comprises cyclisation of4-sulfophthalic acid or an analogue thereof.

The compounds and salts thereof of Formula (1) have attractive, strongcyan shades and are valuable colorants for use in the preparation ofink-jet printing inks. They benefit from a good balance of solubility,storage stability and fastness to water and light.

According to a second aspect of the present invention there is provideda composition comprising a compound of Formula (1) as described in thefirst aspect of the invention and a liquid medium.

Preferred liquid media include water, a mixture of water and organicsolvent and organic solvent free from water. Preferably the liquidmedium comprises a mixture of water and organic solvent or organicsolvent free from water.

When the liquid medium (b) comprises a mixture of water and organicsolvent, the weight ratio of water to organic solvent is preferably from99:1 to 1:99, more preferably from 99:1 to 50:50 and especially from95:5 to 80:20.

It is preferred that the organic solvent present in the mixture of waterand organic solvent is a water-miscible organic solvent or a mixture ofsuch solvents. Preferred water-miscible organic solvents includeC₁₋₆-alkanols, preferably methanol, ethanol, n-propanol, isopropanol,n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol andcyclohexanol; linear amides, preferably dimethylformamide ordimethylacetamide; ketones and ketone-alcohols, preferably acetone,methyl ether ketone, cyclohexanone and diacetone alcohol; water-miscibleethers, preferably tetrahydrofuran and dioxane; diols, preferably diolshaving from 2 to 12 carbon atoms, for example pentane-1,5-diol, ethyleneglycol, propylene glycol, butylene glycol, pentylene glycol, hexyleneglycol and thiodiglycol and oligo- and poly-alkyleneglycols, preferablydiethylene glycol, triethylene glycol, polyethylene glycol andpolypropylene glycol; triols, preferably glycerol and 1,2,6-hexanetriol;mono-C₁₋₄-alkyl ethers of diols, preferably mono-C₁₋₄-alkyl ethers ofdiols having 2 to 12 carbon atoms, especially 2-methoxyethanol,2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)-ethanol,2-[2-(2-methoxyethoxy)ethoxy]ethanol,2-[2-(2-ethoxyethoxy)-ethoxy]-ethanol and ethyleneglycol monoallylether;cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone,N-ethyl-2-pyrrolidone, caprolactam and 1,3-dimethylimidazolidone; cyclicesters, preferably caprolactone; sulfoxides, preferably dimethylsulfoxide and sulfolane. Preferably the liquid medium comprises waterand 2 or more, especially from 2 to 8, water-miscible organic solvents.

Especially preferred water-miscible organic solvents are cyclic amides,especially 2-pyrrolidone, N-methyl-pyrrolidone and N-ethyl-pyrrolidone;diols, especially 1,5-pentane diol, ethyleneglycol, thiodiglycol,diethyleneglycol and triethyleneglycol; and mono-C₁₋₄-alkyl andC₁₋₄-alkyl ethers of diols, more preferably mono- C₁₋₄-alkyl ethers ofdiols having 2 to 12 carbon atoms, especially2-methoxy-2-ethoxy-2-ethoxyethanol.

Examples of further suitable liquid media comprising a mixture of waterand one or more organic solvents are described in U.S. Pat. No.4,963,189, U.S. Pat. No. 4,703,113, U.S. Pat. No. 4,626,284 andEP-A425,150.

When the liquid medium comprises organic solvent free from water, (i.e.less than 1% water by weight) the solvent preferably has a boiling pointof from 30° to 200° C., more preferably of from 40° to 150° C.,especially from 50 to 125° C. The organic solvent may bewater-immiscible, water-miscible or a mixture of such solvents.Preferred water-miscible organic solvents are any of thehereinbefore-described water-miscible organic solvents and mixturesthereof. Preferred water-immiscible solvents include, for example,aliphatic hydrocarbons; esters, preferably ethyl acetate; chlorinatedhydrocarbons, preferably CH₂Cl₂; and ethers, preferably diethyl ether;and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent,preferably a polar solvent is included because this enhances solubilityof the mixture of phthalocyanine dyes in the liquid medium. Examples ofpolar solvents include C₁₋₄-alcohols.

In view of the foregoing preferences it is especially preferred thatwhere the liquid medium is organic solvent free from water it comprisesa ketone (especially methyl ethyl ketone) and/or an alcohol (especiallya C₁₋₄-alkanol, more especially ethanol or propanol).

The organic solvent free from water may be a single organic solvent or amixture of two or more organic solvents. It is preferred that when theliquid medium is organic solvent free from water it is a mixture of 2 to5 different organic solvents. This allows a liquid medium to be selectedthat gives good control over the drying characteristics and storagestability of the ink.

Liquid media comprising organic solvent free from water are particularlyuseful where fast drying times are required and particularly whenprinting onto hydrophobic and non-absorbent substrates, for exampleplastics, metal and glass.

Preferred compositions according to the second aspect of the inventioncomprise:

-   -   (a) from 0.01 to 30 parts of a compound of Formula (1) according        to the first aspect of the invention; and    -   (b) from 70 to 99.99 parts of a liquid medium;        wherein all parts are by weight

Preferably the number of parts of (a)+(b)=100.

The number of parts of component (a) is preferably from 0.1 to 20, morepreferably from 0.5 to 15, and especially from 1 to 5 parts. The numberof parts of component (b) is preferably from 80 to 99.9, more preferablyfrom 85 to 99.5, especially from 95 to 99 parts.

Preferably component (a) is completely dissolved in component (b).Preferably component (a) has a solubility in component (b) at 20° C. ofat least 10%. This allows the preparation of liquid dye concentratesthat may be used to prepare more dilute inks and reduces the chance ofthe dye precipitating if evaporation of the liquid medium occurs duringstorage.

The liquid media may of course contain additional componentsconventionally used in ink-jet printing inks, for example viscosity andsurface tension modifiers, corrosion inhibitors, biocides, kogationreducing additives and surfactants which may be ionic or non-ionic.

Although not usually necessary, further colorants may be added to theink to modify the shade and performance properties. Examples of suchcolorants include C.I. Direct Yellow 86, 132, 142 and 173; C.I. DirectBlue 307; C.I. Food Black 2; C.I. Direct Black 168 and 195; and C.I.Acid Yellow 23.

It is preferred that the composition according to the invention is inksuitable for use in an ink-jet printer. Ink suitable for use in anink-jet printer is ink which is able to repeatedly fire through anink-jet printing head without causing blockage of the fine nozzles.

Ink suitable for use in an ink-jet printer preferably has a viscosity ofless than 20 cP, more preferably less than 10 cP, especially less than 5cP, at 25° C.

Ink suitable for use in an ink-jet printer preferably contains less than500 ppm, more preferably less than 250 ppm, especially less than 100ppm, more especially less than 10 ppm in total of divalent and trivalentmetal ions (other than any divalent and trivalent metal ions bound to acolorant of Formula (1) or any other colourant or additive incorporatedin the ink).

Preferably ink suitable for use in an ink-jet printer has been filteredthrough a filter having a mean pore size below 10 μm, more preferablybelow 3 μm, especially below 2 μm, more especially below 1 μm. Thisfiltration removes particulate matter that could otherwise block thefine nozzles found in many ink-jet printers.

Preferably ink suitable for use in an ink-jet printer contains less than500 ppm, more preferably less than 250 ppm, especially less than 100ppm, more especially less than 10 ppm in total of halide ions.

The inks may be incorporated in an ink-jet printer as a highconcentration cyan ink, a low concentration cyan ink or both a highconcentration and a low concentration ink. In the latter case this canlead to improvements in the resolution and quality of printed images.Thus the present invention also provides a composition (preferably anink) where component (a) is present in an amount of 2.5 to 7 parts, morepreferably 2.5 to 5 parts (a high concentration ink) or component (a) ispresent in an amount of 0.5 to 2.4 parts, more preferably 0.5 to 1.5parts (a low concentration ink).

A third aspect of the invention provides a process for forming an imageon a substrate comprising applying ink suitable for use in an ink-jetprinter, according to the second aspect of the invention, thereto bymeans of an ink-jet printer.

The ink-jet printer preferably applies the ink to the substrate in theform of droplets that are ejected through a small orifice onto thesubstrate. Preferred ink-jet printers are piezoelectric ink-jet printersand thermal ink-jet printers. In thermal ink-jet printers, programmedpulses of heat are applied to the ink in a reservoir by means of aresistor adjacent to the orifice, thereby causing the ink to be ejectedfrom the orifice in the form of small droplets directed towards thesubstrate during relative movement between the substrate and theorifice. In piezoelectric ink-jet printers the oscillation of a smallcrystal causes ejection of the ink from the orifice. Alternately the inkcan be ejected by an electromechanical actuator connected to a moveablepaddle or plunger, for example as described in International PatentApplication WO00/48938 and International Patent Application WO00/55089.

The substrate is preferably paper, plastic, a textile, metal or glass,more preferably paper, an overhead projector slide or a textilematerial, especially paper.

Preferred papers are plain or treated papers which may have an acid,alkaline or neutral character. Glossy papers are especially preferred.Photographic quality papers are especially preferred.

Examples of commercially available premium papers include HP PremiumCoated Paper, HP Photopaper™ (both available from Hewlett Packard Inc.);Stylus™ Pro 720 dpi Coated Paper, Epson Photo Quality™ Glossy Film,Epson Photo Quality™ Glossy Paper (all available from Seiko EpsonCorp.); Canon HR 101 High Resolution™ Paper, Canon GP 201 Glossy™ Paper,Canon HG 101 and HG201 High Gloss™ Film, Canon PR101 (all available fromCanon); Kodak Premium™ Photopaper, Kodak Premium™ InkJetpaper (availablefrom Kodak); Konica Inkjet Paper QP™ Professional Photo Glossy, KonicaInkjet Paper QP™ Professional Photo 2-sided Glossy, Konica Inkjet PaperQP™ Premium Photo Glossy, Konica Inkjet Paper QP™ Premium Photo Silky(available from Konica).

A fourth aspect of the present invention provides a material preferablypaper, plastic, a textile, metal or glass, more preferably paper, anoverhead projector slide or a textile material, especially paper moreespecially plain, coated or treated papers printed with a compound asdescribed in the first aspect of the invention, a composition asdescribed in the second aspect of the invention or by means of a processas described in the third aspect of the invention.

It is especially preferred that the printed material of the fourthaspect of the invention is a print on a photographic quality paperprinted using a process as described in the third aspect of theinvention.

A fifth aspect of the present invention provides an ink-jet printercartridge comprising a chamber and an ink suitable for use in an ink-jetprinter wherein the ink is in the chamber and the ink is as defined inthe second aspect of the present invention. The cartridge may contain ahigh concentration ink and a low concentration ink, as described in thesecond aspect of the invention, in different chambers.

A sixth aspect of the invention provides an amine of Formula (5) andsalts thereof:

The invention is further illustrated by the following Examples in whichall parts and percentages are by weight unless otherwise stated.

EXAMPLES Analysis of Dyes of Formula (1)

Confirmation of the number of substituents on dyes of Formula (1) is bymass spectrometry. Elemental analysis is used to determine the ratios ofx to y+z. Thus, when the sum of x plus y and z is not exactly 4 this isthought to be due to the presence of impurities. The presence of theseimpurities and their effect on the estimated values of x, y and z wouldbe well known to a person skilled in the art who would treat theexperimentally determined values of x, y and z simply as indicative ofthe presence of these substituents. Also with some dyes according to thepresent invention it is not possible, using these methods, todiscriminate between the different sulfonamide substituents. In thesecases x and y are quoted as a sum of both sulfonamide groups i.e. (y+z).

Example 1 Preparation of

Stage 1 Preparation of Copper Phthalocyanine Tetra-β-Sulfonate

Potassium 4-sulfophthalic acid (56.8 g), urea (120 g), CuCl₂ (6.9 g),ammonium molybdate (1.2 g) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)(7.5 g) were mixed in a reaction vessel. The mixture was warmed instages (130° C./30 minutes, 150° C./30 minutes, 180° C./30 minutes, 220°C./30 minutes) over 2 hours and the melt which formed was stirred at220° C. for a further 2 hours. The resultant solid was extracted 4 timeswith hot water (4×200 ml) and the extract was filtered to removeinsoluble material. The filtrate was stirred at between 60° C.-70° C.and then sufficient NaCl was added to give a 7% salt solution. Stirringwas continued and the precipitate was filtered, washed with a 10% saltsolution (200 ml) and pulled dry by vacuum. The resultant damp solid(77.6 g) was slurried in acetone, filtered and dried, first at roomtemperature and then at 50° C.

Stage 2 Preparation of Amine A:

Cyanuric chloride (27.68 g) dissolved in actone (150 ml) was added to aslurry of ice/water (100 g/150 ml) at 0-5° C. A solution of2,5-disulfoaniline (41.4 g) in water (150 ml) at pH 4 to 5 was thenadded dropwise. This reaction mixture was kept below 5° C. and stirredat pH 4 to 5 for 2 hrs. The pH was then adjusted to pH 7 with 2M sodiumhydroxide, the temperature was raised to 20-25° C. and the reactionmixture was left for 1 hour. Ammonia (9.1 ml) was then added and the pHadjusted to pH 9 to 9.5 (with 2M sodium hydroxide) and the reactionmixture was stirred at room temperature overnight. The next day thereaction mixture was heated to 80° C. for 1 h, and then ethylenediamine(99 ml) was added and the reaction mixture was heated at 80° C. for afurther 2 hrs. The reaction mixture was then cooled, sodium chloride wasadded to give a 20% solution, and the pH was lowered to 1 withconcentrated HCl. The precipitate that formed was filtered off andwashed with a 20% sodium chloride solution. The precipitate was thenslurried in methanol at 60° C., filtered and dried to give the aboveproduct (56.1 g).

Stage 3 Preparation of the Title Product

Phosphorous oxychloride (5.16 g) was added dropwise to chlorosulfonicacid (86 g) over 5 to 10 minutes while keeping the temperature below 35°C. When all the Phosphorous oxychloride had been added copperphthalocyanine tetra-β-sulfonate, from Stage 1, (16 g) was addedportion-wise while keeping the reaction temperature below 55° C. Thereaction mixture was stirred at 50-60° C. for 15-20 minutes. Thetemperature of the reaction mixture was then gradually increased to138-140° C. over 30 minutes, held at this temperature for 6.5 h and thenthe reaction mixture was allowed to cool and stirred overnight at roomtemperature. The mixture was added to a water/ice (100 ml/150 g) mixtureand the resultant precipitate was filtered, washed with ice cold waterand filtered. The dried solid (5 g) in water (200 ml) was then added toa mixture of amine A from Stage 2 (2 molar equivalents, 2.94 g), inwater (50 ml) followed by one molar equivalent of2,3-dihydroxypropylamine (0.33 g) at 0°-5° C. The resultant mixture wasstirred at 0° to 5° C. and pH 9 to 9.5 for 1 hour maintaining the pH bythe addition of 2M sodium hydroxide. The reaction mixture was thenstirred at room temperature overnight. The next day the reaction mixturewas heated to 60° C., held at this temperature for 1 hour and thencooled to 40° C. The reaction mixture was then salted with a 20% sodiumchloride solution and the pH was lowered to pH 1 with concentrated HCl.The solid that precipitated was filtered, washed with a 20% solution ofsodium chloride, dissolved in deionised water, dialysed, filtered andthen dried at 70° C. to give the product. Elemental analysis of theproduct gave x=0.7 and (y+z)=3.2.

Example 2 Preparation of

The dye of Example 2 was prepared as described in Example 1 except thatin Stage 3 one molar equivalent of 2,3-dihydroxypropylamine and onemolar equivalents of amine A, from Stage 2, were used. Elementalanalysis of the product gave x=2.2 and (y+z)=1.6.

Example 3 Preparation of

The dye of Example 3 was prepared as described in Example 1 except thatin Stage 3 one molar equivalent of 2-hydroxyethylamine was used in placeof 2,3-dihydroxypropylamine and one molar equivalent of amine A, fromStage 2, was used. Elemental analysis of the product gave x=3.4 and(y+z)=1.8.

Example 4 Preparation of

The dye of Example 4 was prepared as described in Example 1 except thatin Stage 3 one molar equivalent of 2-hydroxyethylamine was used in placeof 2,3-dihydroxypropylamine and two molar equivalents of amine A, fromStage 2, were used. Elemental analysis of the product gave x=1.8 and(y+z)=2.8.

Example 5 Preparation of

The dye of Example 5 was prepared as described in Example 1 except thatin Stage 3 one molar equivalent of taurine was used in place of2,3-dihydroxypropylamine and two molar equivalents of amine A, fromStage 2, were used. Elemental analysis of the product gave x=0.3 and(y+z)=3.4.

Example 6 Preparation of

The dye of Example 6 was prepared as described in Example 1 except thatin Stage 3 one molar equivalent of taurine was used in place of2,3-dihydroxypropylamine, in Stage 2, 3-sulfoaniline was used in placeof 2,5-disulfoaniline and two molar equivalents of amine A, from Stage2, were used in Stage 3. Elemental analysis of the product gave x=1.8and (y+z)=2.2.

Examples 7 to 14

The dyes of Example 7 to 14 were prepared as described in Example 1except that in Stage 3 the two amines used were as specified in thetable below.

Preparation of Amine B

Amine B was prepared as in Example 1, stage 2 except dimethylamine wasused in place of ammonia.

Amidation pH and Example Amine B Amine alkali used x y + z 7 1 molar2,3- 9-9.5 0.1 2.6 equivalent dihydroxypropylamine 2 M NaOH 1 molarequivalent 8 1 molar 2,3- 9-9.5 equivalent dihydroxypropylamine 2 M NaOH4 molar equivalent 9 1 molar 2,3- 9-9.5 0.2 2.4 equivalentdihydroxypropylamine 20% aq. (excess) 2,3-dihydroxypropylamine 10 0.5molar 2,3- 9-9.5 equivalent dihydroxypropylamine 2 M NaOH 4 molarequivalent 11 1 molar 2-hydroxyethylamine 9-9.5 1.4 1.8 equivalent 1molar equivalent 2 M NaOH 12 1 molar 2-hydroxyethylamine 9-9.5 0.7 1.6equivalent 4 molar equivalent 2 M NaOH 13 0.5 molar 2-hydroxyethylamine9-9.5 2.0 1.4 equivalent 4 molar equivalent 2 M NaOH 14 1 molar2-hydroxyethylamine 9-9.5 2.2 1.2 equivalent (excess) 20% aq.2-hydroxyethylamine

Examples 15 to 21

The dyes of Example 15 to 21 were prepared as described in Example 1except that in Stage 3 the two amines used were as specified in thetable below.

Preparation of Amine C

Amine C was prepared as in Example 1, stage 2 except 2-hydroxyethylaminewas used in place of ammonia.

Amidation pH and Example Amine C Amine alkali used x y + z 15 1 molar2-hydroxyethylamine 9-9.5 2.0 1.8 equivalent excess 30% aq.2-hydroxyethylamine 16 1 molar 2-hydroxyethylamine 9-9.5 1.1 1.6equivalent 3 molar equivalent 2 M NaOH 17 1 molar 2-hydroxyethylamine8.5-9 2.3 1.6 equivalent 1 molar equivalent 2 M NaOH 18 2 molar2-hydroxyethylamine 8.5-9 2.4 1.6 equivalent 2 molar equivalent 2 M NaOH19 2 molar 2-hydroxyethylamine 9-9.5 2.2 1.4 equivalent 1 molarequivalent 2 M NaOH 20 1 molar 2,3-dihydroxypropylamine 9-9.5 1.1 2.0equivalent 1 molar equivalent 2 M NaOH 21 1 molar2,3-dihydroxypropylamine 9-9.5 1.5 1.4 equivalent 4 molar equivalent 2 MNaOH

Example 22

Prepared as in Example 1, stage 2 except 2,3-dihydroxypropylamine wasused in place of ammonia.

Examples 23 to 26

Amine of Example Example 22 Amine pH x y + z 23 1 molar 2,3- 9-9.5 1.61.6 equivalent dihydroxypropylamine 2M NaOH 4 molar equivalent 24 1molar 2,3- 9-9.5 1.4 2.0 equivalent dihydroxypropylamine 2M NaOH 1 molarequivalent 25 1 molar 2-hydroxyethylamine 9-9.5 2.0 1.6 equivalent 1molar equivalent 2M NaOH 26 1 molar 2-hydroxyethylamine 9-9.5 1.7 1.4equivalent 4 molar equivalent 2M NaOH

Comparative Dyes 1 and 2

The comparative dyes were two of the market leading ink-jet cyan dyesPro-Jet® Cyan 1 and Pro-Jet® Cyan 2 available from FUJIFILM ImagingColorants Ltd.

Example 27 Preparation of Inks and Comparative Inks

Inks were prepared from the Comparative Dyes and the dyes of Examples 1,8, 16 and 23 as shown in Table 1, by dissolving 3 g of a dye in 97 ml ofa liquid medium consisting of 5 parts 2-pyrrolidone; 5 partsthiodiethylene glycol; 1 part Surfynol® 465 and 89 parts water andadjusting the pH to between pH 8 to 9 with sodium hydroxide. Surfynol®465 is a surfactant from Air Products.

TABLE 1 Dye of Example Ink Example 1 Example Ink 1 8 Example Ink 2 16Example Ink 3 23 Example Ink 4 Comparative Dye 1 Comparative Ink C1Comparative Dye 2 Comparative Ink C2

Example 28 Ink-Jet Printing

Inks prepared as described above were filtered through a 0.45 micronnylon filter and then incorporated into empty print cartridges using asyringe.

These inks were then printed onto Epson Ultra Premium Glossy Photo Paper(SEC PM) and Canon Premium PR101 Photo Paper (PR101).

The prints so formed, at 70% depth, were tested for ozone fastness byexposure to 1 ppm ozone at 40° C., 50% relative humidity for 24 hrs in aHampden 903 Ozone cabinet. Fastness of the printed ink to ozone isjudged by the difference in the optical density before and afterexposure to ozone.

Optical density measurements were performed using a Gretag spectrolinospectrophotometer set to the following parameters:

Measuring Geometry 0°/45° Spectral Range 380-700 nm Spectral Interval 10nm Illuminant D65 Observer 2° (CIE 1931) Density Ansi A External FillerNone

Ozone fastness was assessed by the percentage change in the opticaldensity of the print, where a lower figure indicates higher fastness.Results are shown in Table 2

TABLE 2 Ink Example SEC PM PR 101 Example Ink 1 15.04 9.09 Example Ink 25.69 3.76 Example Ink 3 3.82 1.42 Example Ink 4 7.63 5.07 ComparativeInk C1 52.94 38.98 Comparative Ink C2 54.17 39.16

Table 2 shows that the ink of the present invention have higher ozonefastness than the comparative dyes.

Further Inks

The inks described in Tables A and B may be prepared wherein theCompound described in the first column is the Compound made in the aboveExample of the same number. Numbers quoted in the second column onwardsrefer to the number of parts of the relevant ingredient and all partsare by weight. The inks may be applied to paper by thermal or piezoink-jet printing.

The following abbreviations are used in Tables A and B:

PG=propylene glycol

DEG=diethylene glycol

NMP=N-methylpyrrolidone

DMK=dimethylketone

IPA=isopropanol

MEOH=methanol

2P=2-pyrrolidone

MIBK=methylisobutyl ketone

P12=propane-1,2-diol

BDL=butane-2,3-diol

CET=cetyl ammonium bromide

PHO=Na₂HPO₄ and

TBT=tertiary butanol

TDG=thiodiglycol

TABLE A Dye Na Example Content Water PG DEG NMP DMK NaOH Stearate IPAMEOH 2P MIBK 1 2.0 80 5 6 4 5 2 3.0 90 5 5 0.2 3 10.0 85 3 3 3 5 1 4 2.191 8 1 5 3.1 86 5 0.2 4 5 6 1.1 81 9 0.5 0.5 9 1 2.5 60 4 15 3 3 6 10 54 2 5 65 20 10 1 2.4 75 5 4 5 6 5 2 4.1 80 3 5 2 10 0.3 1 3.2 65 5 4 6 54 6 5 1 5.1 96 4 1 10.8 90 5 5 1 10.0 80 2 6 2 5 1 4 1 1.8 80 5 15 1 2.684 11 5 1 3.3 80 2 10 2 6 1 12.0 90 7 0.3 3 1 5.4 69 2 20 2 1 3 3 1 6.091 4 5

TABLE B Dye Example Content Water PG DEG NMP CET TBT TDG BDL PHO 2P PI21 3.0 80 15 0.2 5 2 9.0 90 5 1.2 5 3 1.5 85 5 5 0.15 5.0 0.2 4 2.5 90 64 0.12 5 3.1 82 4 8 0.3 6 6 0.9 85 10 5 0.2 1 8.0 90 5 5 0.3 2 4.0 70 104 1 4 11 1 2.2 75 4 10 3 2 6 1 10.0 91 6 3 1 9.0 76 9 7 3.0 0.95 5 1 5.078 5 11 6 1 5.4 86 7 7 1 2.1 70 5 5 5 0.1 0.2 0.1 5 0.1 5 1 2.0 90 10 12 88 10 1 5 78 5 12 5 1 8 70 2 8 15 5 1 10 80 8 12 1 10 80 10

1. Compounds of Formula (1) and salts thereof:

wherein: M is 2H, Si, a metal, an oxymetal group, a hydroxymetal groupor a halometal group; Pc represents a phthalocyanine nucleus of formula;

R¹ is optionally substituted alkyl other than methyl; R² is H,optionally substituted alkyl or optionally substituted aryl; R³ is H,optionally substituted alkyl or optionally substituted aryl; R⁴ is agroup comprising a heterocycle and an ionisable group; L is a directbond or a divalent linking group; x is 0.1 to 3.8; y is 0.1 to 3.8; andz is 0.1 to 3.8.
 2. Compounds and salts thereof according to claim 1wherein M is Cu.
 3. Compounds and salts thereof according to claim 1wherein R¹ is optionally substituted C₂₋₆alkyl.
 4. Compounds and saltsthereof according to claim 1 wherein R¹ carries at least one substituentselected from the group consisting of —OH, —SO₃H, —CO₂H and —PO₃H₂. 5.Compounds and salts thereof according to claim 1 wherein R² is H ormethyl.
 6. Compounds and salts thereof according to claim 1 wherein R³is H or methyl.
 7. Compounds and salts thereof according to claim 1wherein R⁴ comprises a nitrogen heterocycle.
 8. Compounds and saltsthereof according to claim 1 wherein R⁴ comprises an ionisable acidgroup selected from the group consisting of —SO₃H, —CO₂H and —PO₃H₂. 9.Compounds and salts thereof according to claim 1 wherein R⁴ is atriazinyl radical bearing substituents selected from the groupconsisting of —SO₃H, —CO₂H and —PO₃H₂.
 10. Compounds and salts thereofaccording to claim 1 wherein R⁴ comprises a group of Formula (2)

wherein: X is selected from the group consisting of —OR⁵, —SR⁵, —NR⁵R⁶;Y is selected from the group consisting of —OR⁷, —SR⁷, —NR⁷R⁸; R⁵, R⁶,R⁷ and R⁸ are independently H, optionally substituted alkyl, optionallysubstituted aryl or optionally substituted heterocyclyl provided that atleast one of the groups represented by R⁵, R⁶, R⁷ and R⁸ carries atleast one substituent selected from the group consisting of —SO₃H, —CO₂Hand —PO₃H₂.
 11. Compounds and salts thereof according to claim 1 whereinR⁴ comprises a group of Formula (3)

wherein: R⁹ is H or optionally substituted C₁₋₄alkyl; R¹⁰ is H oroptionally substituted C₁₋₄alkyl; R¹¹ is H or optionally substitutedC₁₋₄alkyl; R¹² is optionally substituted alkyl, optionally substitutedaryl or optionally substituted heterocyclyl carrying at least onesubstituent selected from the group consisting of —SO₃H, —CO₂H and—PO₃H₂.
 12. Compounds and salts thereof according to claim 1 wherein Lcomprises optionally substituted alkylene.
 13. Compounds and saltsthereof according to claim 1 wherein L comprises a group of formula—C₁₋₄alkylene-Z; where Z is a hetero atom.
 14. Compounds and saltsthereof according to claim 1 wherein L comprises a group of formula—C₂H₄—NR²⁰—, wherein R²⁰ is H or methyl.
 15. Compounds and salts thereofaccording to claim 1 wherein (x+y+z) is
 4. 16. Compounds according toclaim 1 of Formula (4) and salts thereof

wherein: R¹³ is optionally substituted C₂₋₄alkyl; R¹⁴, R¹⁵, R¹⁶, R¹⁷ andR¹⁸ are each independently H or methyl; R¹⁹ is aryl carrying 1 to 3—SO₃Hgroups and other optional substituents; R²⁰ is H or methyl; L′ isoptionally substituted C₁₋₄alkylene; x is 0.1 to 3.8; y is 0.1 to 3.8; zis 0.1 to 3.8; and x+y+z is in the range of 3 to
 4. 17. Compounds andsalts thereof according to claim 1 wherein the substituents representedby x, y and z are bound to the phthalocyanine ring only through the□-position on the phthalocyanine ring.
 18. A composition comprising acompound of Formula (1) as described in claim 1 and a liquid medium. 19.A composition according to claim 18 wherein the liquid medium comprisesa mixture of water and organic solvent or organic solvent free fromwater.
 20. A composition according to claim 18 which is ink suitable foruse in an ink-jet printer.
 21. A process for forming an image on asubstrate comprising applying ink suitable for use in an ink-jetprinter, according to claim 20, thereto by means of an ink-jet printer.22. A material printed with a compound as described in claim
 1. 23. Amaterial according to claim 22 which is a print on a photographicquality paper printed using a process as described in claim
 21. 24. Anink-jet printer cartridge comprising a chamber and an ink suitable foruse in an ink-jet printer wherein the ink is in the chamber and the inkis as defined in claim
 20. 25. An amine of Formula (5) and saltsthereof: